Konversikan data kolom perbedaan TIMESTAMP ke format string

Saat Anda menambah atau mengurangi stempel waktu, hasilnya adalah interval , bukan stempel waktu lainnya. Anda dapat menggunakan extract fungsi untuk menarik komponen keluar dari itu. Jika nilai Anda akan selalu menjadi sub-detik, Anda cukup mengekstrak detik, dan mengalikannya dengan seribu untuk mendapatkan milidetik:

with t as (
  select 1 as msg_guid,
    interval '0 0:0:0.343009' day to second as diff
  from dual
)
select trunc(extract (second from diff) * 1000)
from t;

TRUNC(EXTRACT(SECONDFROMDIFF)*1000)
-----------------------------------
                                343 

Di sini kueri Anda yang sebenarnya akan menggantikan CTE dummy yang saya gunakan dengan literal interval.

Jika intervalnya mungkin lebih dari satu detik maka Anda mungkin ingin mendapatkan seluruh nilai dalam milidetik, jadi Anda perlu mengekstrak semua elemen dan menambahkannya bersama-sama, mengalikan masing-masing berdasarkan apa yang mereka wakili - jadi sehari penuh akan menjadi 8640000 milidetik dll .; elemen polos akan keluar seperti:

column diff format a25
with t as (
  select 1 as msg_guid,
    systimestamp - trunc(systimestamp) as diff
  from dual
)
select diff,
  extract (day from diff) as dd,
  extract (hour from diff) as hh,
  extract (minute from diff) as mi,
  extract (second from diff) as ss
from t;

DIFF                           DD         HH         MI         SS
---------------------- ---------- ---------- ---------- ----------
0 9:13:26.150627                0          9         13  26.150627 

Dan Anda akan menggabungkannya seperti:

with t as (
  select 1 as msg_guid,
    systimestamp - trunc(systimestamp) as diff
  from dual
)
select diff,
  trunc(1000 * (
    extract (day from diff) * (60*60*24)
    + extract (hour from diff) * (60*60)
    + extract (minute from diff) * 60
    + extract (second from diff)
  )) as milliseconds
from t;

DIFF                   MILLISECONDS
---------------------- ------------
0 9:13:27.650365           33207650 

Tetapi berdasarkan pertanyaan Anda sebelumnya, mungkin Anda menginginkannya sebagai string, sebagai komponen terpisah:

with t as (
  select 1 as msg_guid,
    systimestamp - trunc(systimestamp) as diff
  from dual
)
select diff,
  extract (day from diff) || ' DAYS '
    || extract (hour from diff) || ' HOURS '
    || extract (minute from diff) || ' MINUTES '
    || trunc(extract (second from diff)) || ' SECONDS '
    || (trunc(extract (second from diff) * 1000)
      - (trunc(extract (second from diff)) * 1000)) || ' MILLISECONDS'
    as text
from t;

DIFF                   TEXT                                                   
---------------------- -------------------------------------------------------
0 9:43:38.896007       0 DAYS 9 HOURS 43 MINUTES 38 SECONDS 896 MILLISECONDS

SQL Fiddle berdasarkan data sampel Anda, semacamnya, dan dengan penghitungan waktu terbalik sehingga nilainya positif.